In GSM communications networks (GSM=Global System for Mobile Communication), communications links which are, for example, directed to a communications terminal (mobile) and incur charges for a charge account associated with the communications terminal can be set up. This occurs, for example, when the communications terminal is outside its home communications network (HPLMN=Home Public Land Mobile Network) and is activated (registered) in a foreign communications network (e.g. abroad). If the communications terminal is called from the home communications network, the call is forwarded from the home communications network to the foreign communications network (roaming). In this case, the caller only pays charges at a level which is normal in the home communications network for calls within the network. Additionally, the charge account associated with the communications terminal which is in the foreign communications network is billed additional charges for forwarding the call to the foreign communications network.
For the communications terminal activated in the foreign communications network, a “call forwarding service” can be used in the home communications network. It is then possible for a network node in the home communications network, which has a sequence control function and a forwarding sequence control function, to take the setup request for the communications link as a basis for performing sequence steps for setting up the communications link. It is also possible for the network node to take the existence of the call forwarding service as a basis for performing forwarding sequence steps for setting up a forwarding communications link.
On the basis of the call forwarding service, the communications link (for example, from the home communications network to the foreign communications network) which incurs charges for the communications terminal is not actually set up. Instead, a forwarding communications link to a destination prescribed by the call forwarding service is set up. Since the network node in the (home) communications network performs the sequence steps for setting up the charge-incurring communications link, however, it is possible for these sequence steps to carry out charging for this charge-incurring communications link.